A5030620483- Photosynthetic Processes and Mechanisms
- Biocrusts and Microbial Ecology
- Chemical Reactions and Isotopes
- Aquatic Ecosystems and Phytoplankton Dynamics
- DNA and Nucleic Acid Chemistry
- Diatoms and Algae Research
Abstract In cyanobacteria DNA supercoiling varies over the diurnal light/dark cycle and is integrated with circadian transcription program (Woelfle et al. [2007], Vijayan [2009], PNAS). Specifically, Woelfle al . have reported that of an endogenous plasmid became progressively higher during prolonged dark phases in Synechococcus elongatus PCC 7942. This counterintuitive, since levels negative are commonly associated exponential growth high metabolic flux. then reverted interpretation...
Supercoiling plays a major role in the regulation of bacterial growth, especially circadian rhythm cyanobacteria. The Keller's Band Counting Method was modified with use intercalating substance chloroquine (CQ), instead using ethidium bromide (EthBr). principle that method is to conserve supercoils through intercalation and unwinding not intercalated Topoisomerase I. Using different concentrations cause levels supercoiling. treated samples were applied on agarose gels containing as well....
DNA is not only separated by size, but also conformation. This can be used as advantage when it comes to separate and visualize topoisomers of the same plasmid: more supercoiled a plasmid, compact is. A standard agarose gel shows plasmid one blurred band; adding an intercalating agent such ethidium bromide or chloroquine resolve this. Chloroquine able unwind locally, releasing torsional stress neutralizing negative supercoils, even introducing positive supercoils. circumstance alters...